US4001594A - Method for controlling the quantity of exposure in photographic printing - Google Patents

Method for controlling the quantity of exposure in photographic printing Download PDF

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Publication number
US4001594A
US4001594A US05/588,984 US58898475A US4001594A US 4001594 A US4001594 A US 4001594A US 58898475 A US58898475 A US 58898475A US 4001594 A US4001594 A US 4001594A
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Prior art keywords
density
exposure
negative film
value
controlling
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Expired - Lifetime
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US05/588,984
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English (en)
Inventor
Taizo Akimoto
Takaaki Terasita
Shigeru Watanabe
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Fujifilm Holdings Corp
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Fuji Photo Film Co Ltd
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    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B27/00—Photographic printing apparatus
    • G03B27/72—Controlling or varying light intensity, spectral composition, or exposure time in photographic printing apparatus
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B27/00—Photographic printing apparatus
    • G03B27/72—Controlling or varying light intensity, spectral composition, or exposure time in photographic printing apparatus
    • G03B27/80—Controlling or varying light intensity, spectral composition, or exposure time in photographic printing apparatus in dependence upon automatic analysis of the original

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  • the present invention relates to a method for controlling the quantity of exposure in photographic printing, wherein, in a process of negative and positive photographic printing, a maximum density and a minimum density of a negative photographic film are measured, which are used with tonal signals obtained therefrom to obtain prints printed to have a proper printing density even from a negative film having principal subject density failures.
  • FIGS. 1 to 3 illustrate the density distributions of the image plane, in which the relative sensitivity of a typical amateur negative film with respect to various colors is measured in a ratio of 1:1:1, where the abscissa represents the density and the ordinate represents the number of portions having the respective density.
  • FIG. 1 shows what is called a "PROPER NEGATIVE" density distribution, in which a good print is obtained when printing is carried out with the mean transmission density as a reference and which has the characteristics of a regular distribution on the whole, and the density of a principal subject (as indicated by the narrow upwardly pointing arrow) and the mean transmission density (as indicated by the broad downwardly pointing arrow) (hereinafter merely referred to as "mean density”), each density on the whole coinciding with a value in the middle of the distribution.
  • mean density as indicated by the narrow upwardly pointing arrow
  • mean density as indicated by the broad downwardly pointing arrow
  • FIG. 2 shows the density distribution of a portrait with a light background, in which a second peak can be seen on the side of a high density corresponding to an area with a light background.
  • the density of the principal subject has a value greatly different from that of the mean density, and hence a satisfactory print can not be obtained in a process of printing with only the mean density as a reference, resulting in the necessity for correcting the quantities of exposure corresponding to the difference therebetween.
  • FIG. 3 shows the density distribution of a portrait with a dark background, in which a second peak can be seen on the side of a low density corresponding to an area with a dark background.
  • the density of the principal subject has a value greatly different from that of the mean density, and hence a satisfactory print can not be obtained in a process of printing with only the mean density as a reference, resulting in the necessity of correcting the quantity of exposure corresponding to the difference therebetween.
  • a plurality of photoelectric conversion means is arranged over the entire surface of the negative film to obtain the maximum density, the minimum density and the mean density of the negative film, and (1) the mean value between the maximum density and the minimum density and the difference between the maximum density and the minimum density, that is, the tonal differences are calculated therefrom, calculating the approximate sum thereof, or (2) the difference between the above-described mean value and the mean density is calculated and the approximate sum of the above-described maximum density and minimum density difference and the above-described tonal difference is further calculated.
  • either one of the foregoing means is used to control the quantity of printing exposure.
  • the apparatus as described above is superior in some respects to the conventional apparatus for controlling the quantity of printing exposure using only the mean density, while the apparatus has the following disadvantages. That is to say, the quantity of printing exposure is represented, unconditionally, by the approximate sum of the mean value between the maximum density and the minimum density (hereinafter, "intermediate density”) and the difference between the maximum density and the minimum density (hereinafter, “tonal difference”).
  • the apparatus is employed as the apparatus for controlling the quantity of printing exposure which is suitable for printing a negative film photographed under appropriate conditions, it is obvious that a negative film, for example, having the same density of the principal subject as that of the negative film previously described but having a small tonal difference as a whole is subjected to excessive printing exposure, resulting in a failure to obtain a satisfactory print.
  • a negative film photographed under excessive exposure conditions it is obvious that the film lacks exposure, also resulting in a failure to obtain a satisfactory print.
  • the unsatisfactory prints as described above result from a control by the apparatus of the quantity of printing exposure based on the intermediate density of the negative film and the tonal difference.
  • both the intermediate density of the negative film and the tonal difference as described above can serve as information representative of significant characteristics of the negative film, it is not advisable to apply the approximate sum thereof unconditionally to the control of the quantity of printing exposure.
  • the reason is that the intermediate density of the negative film usually represents a value close to the mean density of the negative film, and the effect of the intermediate density and the tonal difference exerted on the density distribution of the negative film is not always considered unconditionally but there are some negative films whose density distribution differs greatly.
  • the present invention provides a novel method for controlling the quantity of printing exposure whose object is to obtain high-quality prints, while removing those disadvantages noted above with respect to prior art apparatus for controlling the quantity of printing exposure.
  • the present invention provides a novel method for controlling the quantity of printing exposure in a photographic printing process comprising photoelectrically measuring the maximum density and the minimum density of a negative photographic film, which are used with tonal signals obtained therefrom to obtain prints printed to have a proper printing density even from a negative film having principal subject density failures.
  • FIGS. 1 to 3 are graphical representations illustrating density distributions on the image plane of a negative film.
  • FIG. 4 is a block diagram showing a mode of an embodiment according to the present invention.
  • FIG. 5 is a curve showing a linear or non-linear conversion.
  • FIG. 6 is a block diagram showing another mode of an embodiment according to the present invention.
  • FIG. 7 shows an embodiment of a photoelectric conversion means.
  • FIG. 8 is a circuit diagram showing means for discriminating the maximum density, minimum density and tone.
  • FIG. 9 is a circuit diagram showing a non-linear conversion means.
  • FIG. 4 is a block diagram showing the concept of the present invention.
  • the reference character X designates a photoelectric conversion means, e.g., means comprising a projector for projecting light through the negative film and light receiving devices for receiving and measuring the amount of light passed, for detecting the density of a negative film
  • Y designates a maximum and minimum density discriminating means
  • C designates a tone discriminating means
  • D designates a means for carrying out a linear or non-linear conversion
  • E designates an addition means.
  • the photoelectric conversion means X detects a plurality of optical density signals from a principal portion of a negative film
  • the maximum and minimum density discriminating means Y discriminates the maximum value (D max) and the minimum value (D min) from the plurality of density signals
  • the tone discriminating means C provides a tonal signal (D max - D min).
  • This tonal signal is converted as shown in FIG. 5 by the linear or non-linear conversion means D, after which the signal is added to the minimum density signal to obtain a printing exposure control signal (D cal).
  • FIG. 7 shows one example of a photoelectric conversion means which comprises a plurality of light receiving devices 3 for detecting the density in various portions corresponding to the principal portion of the negative film, and a multiplexor 4 for obtaining the output from the light receiving devices.
  • the detection of the density in the negative film is limited to a certain area to prevent the printing exposure condition of a principal subject in an ordinary negative film from being affected by the density in the peripheral portions unrelated thereto.
  • the detection area as described above was set in the range of from about 20 to 40% in the central portion of the entire image plane of the negative film.
  • the above-described light receiving devices 3 and the multiplexor 4 are set to detect only the density from those portions as described above of the travelling negative film.
  • FIG. 8 shows one example of a means for obtaining the maximum value of and the minimum value of the output from the photoelectric conversion means, as well as the difference therebetween (tonal signal).
  • the output X from the photoelectric conversion means 3 1 . . . 3 n is successively obtained by the multiplexor, and the maximum value of the output X is discriminated in a circuit A including operational amplifiers OP 1 and OP 2 , the minimum value thereof in a circuit B including operational amplifiers OP 3 and OP 4 , and the difference therebetween (tonal signal) in a circuit C including an operational amplifier OP 5 .
  • FIG. 9 shows one example of a non-linear conversion means as shown in FIG. 5, where I is the input, and O is the output.
  • the slope of the linear portion RS can be controlled by variable resistor VR 2 , the position of point R by variable resistor VR 1 , and the position of point Q by variable resistor VR 3 , respectively.
  • high-quality prints can be obtained by a non-linear conversion of the value of the tonal difference in the negative film, for example, as shown in FIG. 5, even from those negative films which previously have been difficult to obtain high-quality prints in the conventional photographic printing method.
  • the reason is that in the case of a negative film having an extremely large tonal difference, the tonal difference may be clipped at a certain upper limit value to produce an effect in which the quantity of exposure is decreased.
  • a negative film such as those subjected to a super-over exposure or a super-under exposure
  • the above-described feature of the invention is derived from the fact that the output corresponding to the tonal difference may be decreased to produce an effect in which the quantity of exposure is decreased.
  • the present invention provides extremely important effects for practical use by employment of a conversion, in which when the value of the tonal difference exceeds a desirable range (within which a successful result may be obtained in the manner of printing normally), the tonal difference is clipped at the upper limit (e.g., "b" in FIG. 5) in the range as described above, whereas when the value thereof does not reach the above-described range, the output is further decreased.
  • a desirable range within which a successful result may be obtained in the manner of printing normally
  • the tonal difference is clipped at the upper limit (e.g., "b" in FIG. 5) in the range as described above, whereas when the value thereof does not reach the above-described range, the output is further decreased.
  • the results in the above table demonstrate outstanding effects can be achieved where more than two characteristic values are combined, although this may be a result of the fact that the measurement area of various measured values is limited as previously described.
  • the table shows that the characteristic value D mean + 1/2 (D max - D min) analogous to the technique disclosed in Japanese Patent (OPI) No. 34,535/1973 previously referred to, that is, the control of the quantity of printing exposure with the mean density and the tonal difference is also relatively effective, but it can be seen that the former is inferior to the control of the quantity of printing exposure with the minimum density and the tonal difference.
  • the value of D max - D min can be kept at the above-described upper limit and lower limit to attain a higher quality print.
  • photoelectric conversion means X A description of photoelectric conversion means X is given below.
  • a black-and-white negative film no particular problem will arise.
  • the density measurement is carried out with a color negative film, it is necessary to measure the density variation of cyan, magenta and yellow colors, each of which are equally important.
  • the relative sensitivity relative to the respective colors is set at a ratio of 1:1:1 to keep the influence due to the color as small as possible even in a color negative film having what is called a color failure.
  • FIG. 6 is a block diagram showing the concept of the present invention as may be applied to the case hereinabove described.
  • the reference characters X, Y, C and D designate the same means as those employed in FIG. 4,
  • the reference character L designates conventional means for obtaining a mean transmission density signal (D mean),
  • the reference character F designates means for calculating the difference between the printing exposure control signal (D cal) and the mean transmission density signal (D mean).
  • the operation required until the printing exposure control signal (D cal) is obtained can be accomplished in the manner as previously described, and in order to apply the above-described operation to a printer which uses the conventional method for controlling the quantity of printing exposure with the mean transmission density, the difference therebetween is obtained as an output.

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  • Physics & Mathematics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • General Physics & Mathematics (AREA)
  • Control Of Exposure In Printing And Copying (AREA)
  • Silver Salt Photography Or Processing Solution Therefor (AREA)
US05/588,984 1974-06-21 1975-06-20 Method for controlling the quantity of exposure in photographic printing Expired - Lifetime US4001594A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP49071636A JPS5913011B2 (ja) 1974-06-21 1974-06-21 写真焼付露光量制御方法
JA49-71636 1974-06-21

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US4001594A true US4001594A (en) 1977-01-04

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US (1) US4001594A (enrdf_load_stackoverflow)
JP (1) JPS5913011B2 (enrdf_load_stackoverflow)
CH (1) CH597617A5 (enrdf_load_stackoverflow)
DE (1) DE2527591A1 (enrdf_load_stackoverflow)

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4099064A (en) * 1975-11-24 1978-07-04 Gretag Aktiengesellschaft Device for pretesting originals to be copied for their copyability
US4100424A (en) * 1975-08-19 1978-07-11 Fuji Photo Film Co., Ltd. Method for controlling a photographic printing exposure
US4160596A (en) * 1977-10-18 1979-07-10 The United States Of America As Represented By The Secretary Of Commerce Document reproduction illumination/exposure control system
US4168120A (en) * 1978-04-17 1979-09-18 Pako Corporation Automatic exposure corrections for photographic printer
EP0008557A3 (fr) * 1978-08-17 1980-05-28 EASTMAN KODAK COMPANY (a New Jersey corporation) Appareil de tirage photographique en couleurs et procédé de détermination des durées d'exposition
DE2946862A1 (de) * 1978-11-22 1980-06-12 Fuji Photo Optical Co Ltd Lichtmessvorrichtung
EP0016844B1 (en) * 1978-08-16 1983-09-14 Fuji Photo Film Co., Ltd. Method of correcting color of color original picture
US4585352A (en) * 1982-11-03 1986-04-29 Oce-Nederland B.V. System for measuring the optical density of both the background and the image areas of an original
US4653926A (en) * 1981-04-06 1987-03-31 Fuji Photo Film Co., Ltd. Method of detecting blurred photographic originals
US4792830A (en) * 1986-12-05 1988-12-20 Fuji Photo Film Co., Ltd. Method for detecting defocused photographic images and photographic printing device
GB2288669A (en) * 1994-04-20 1995-10-25 Heidelberger Druckmasch Ag Method of controlling the imaging of a printing forme
US5751401A (en) * 1994-11-04 1998-05-12 Fuji Photo Film Co., Ltd. Method of determining amount of exposure
US5816164A (en) * 1994-04-20 1998-10-06 Heidelberger Druckmaschinen Ag Method and apparatus for monitoring image formation on a printing form
US6058202A (en) * 1995-10-06 2000-05-02 Fuji Photo Film Co., Ltd. Method of determining exposure condition of photograph
US20040047514A1 (en) * 2002-09-05 2004-03-11 Eastman Kodak Company Method for sharpening a digital image

Families Citing this family (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5378875A (en) * 1976-12-22 1978-07-12 Kogyosha Tsushin Kiki Seisak Automatic device for detecting concentration correction
DK153426B (da) * 1977-04-12 1988-07-11 Eskofot As Fremgangsmaade til styring kontrasten ved raster eproduktion
JPS6045436B2 (ja) * 1977-05-10 1985-10-09 キヤノン株式会社 記録装置
JPS543395U (enrdf_load_stackoverflow) * 1977-06-11 1979-01-10
JPS5488118A (en) * 1977-12-26 1979-07-13 Ricoh Co Ltd Control device for light amount of copier
JPS5492742A (en) * 1977-12-29 1979-07-23 Ricoh Co Ltd Control method for copier image quality
JPS552230A (en) * 1978-06-19 1980-01-09 Fuji Photo Film Co Ltd Color printer
JPS6025060Y2 (ja) * 1978-06-30 1985-07-27 日本電子株式会社 走査型電子顕微鏡
JPS5630121A (en) * 1979-08-22 1981-03-26 Fuji Photo Film Co Ltd Controlling method of exposure for photographic printing
JPS5745564A (en) * 1980-09-02 1982-03-15 Konishiroku Photo Ind Co Ltd Automatic image quality adjuster in copying machine
DK147954B (da) * 1981-03-31 1985-01-14 Eskofot As Fremgangsmaade og apparat til styring af kontrasten ved reproduktion
US4344699A (en) * 1981-06-05 1982-08-17 Log Etronics, Inc. Exposure and contrast determination by prescanning in electronic photoprinting systems
JPS60181739A (ja) * 1984-02-28 1985-09-17 Fuji Photo Film Co Ltd 放射線画像情報読取条件及び／又は画像処理条件決定方法
JPH0693771B2 (ja) * 1984-10-29 1994-11-16 ソニー株式会社 電子ビ−ム録画装置のビ−ム電流制御回路
JPS6242145A (ja) * 1985-08-20 1987-02-24 Canon Inc 情報記録装置
JPS6258280A (ja) * 1986-08-26 1987-03-13 Ricoh Co Ltd 複写装置の画質調整方法
US4730214A (en) * 1986-09-15 1988-03-08 General Electric Company Method and apparatus for correlating video and film images produced from electronic data

Citations (4)

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US3560757A (en) * 1968-07-22 1971-02-02 Crosfield Electronics Ltd Circuit for generating block-printer signal in color printing apparatus
US3652791A (en) * 1969-01-08 1972-03-28 Xerox Corp Circuitry for distinguishing between background and intelligence areas on a document
US3690765A (en) * 1971-04-13 1972-09-12 Eastman Kodak Co Apparatus for advancing unprintable negatives through photographic printers
US3856413A (en) * 1973-01-18 1974-12-24 P Bey Photographic color densitometer

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS4834535A (enrdf_load_stackoverflow) * 1971-09-06 1973-05-19

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3560757A (en) * 1968-07-22 1971-02-02 Crosfield Electronics Ltd Circuit for generating block-printer signal in color printing apparatus
US3652791A (en) * 1969-01-08 1972-03-28 Xerox Corp Circuitry for distinguishing between background and intelligence areas on a document
US3690765A (en) * 1971-04-13 1972-09-12 Eastman Kodak Co Apparatus for advancing unprintable negatives through photographic printers
US3856413A (en) * 1973-01-18 1974-12-24 P Bey Photographic color densitometer

Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4100424A (en) * 1975-08-19 1978-07-11 Fuji Photo Film Co., Ltd. Method for controlling a photographic printing exposure
US4099064A (en) * 1975-11-24 1978-07-04 Gretag Aktiengesellschaft Device for pretesting originals to be copied for their copyability
US4160596A (en) * 1977-10-18 1979-07-10 The United States Of America As Represented By The Secretary Of Commerce Document reproduction illumination/exposure control system
US4168120A (en) * 1978-04-17 1979-09-18 Pako Corporation Automatic exposure corrections for photographic printer
EP0016844B1 (en) * 1978-08-16 1983-09-14 Fuji Photo Film Co., Ltd. Method of correcting color of color original picture
EP0008557A3 (fr) * 1978-08-17 1980-05-28 EASTMAN KODAK COMPANY (a New Jersey corporation) Appareil de tirage photographique en couleurs et procédé de détermination des durées d'exposition
DE2946862A1 (de) * 1978-11-22 1980-06-12 Fuji Photo Optical Co Ltd Lichtmessvorrichtung
US4653926A (en) * 1981-04-06 1987-03-31 Fuji Photo Film Co., Ltd. Method of detecting blurred photographic originals
US4585352A (en) * 1982-11-03 1986-04-29 Oce-Nederland B.V. System for measuring the optical density of both the background and the image areas of an original
US4792830A (en) * 1986-12-05 1988-12-20 Fuji Photo Film Co., Ltd. Method for detecting defocused photographic images and photographic printing device
GB2288669A (en) * 1994-04-20 1995-10-25 Heidelberger Druckmasch Ag Method of controlling the imaging of a printing forme
GB2288669B (en) * 1994-04-20 1997-12-03 Heidelberger Druckmasch Ag Method of controlling the imaging of a printing forme
US5816164A (en) * 1994-04-20 1998-10-06 Heidelberger Druckmaschinen Ag Method and apparatus for monitoring image formation on a printing form
US5751401A (en) * 1994-11-04 1998-05-12 Fuji Photo Film Co., Ltd. Method of determining amount of exposure
US6058202A (en) * 1995-10-06 2000-05-02 Fuji Photo Film Co., Ltd. Method of determining exposure condition of photograph
US20040047514A1 (en) * 2002-09-05 2004-03-11 Eastman Kodak Company Method for sharpening a digital image
US7228004B2 (en) * 2002-09-05 2007-06-05 Eastman Kodak Company Method for sharpening a digital image

Also Published As

Publication number Publication date
CH597617A5 (enrdf_load_stackoverflow) 1978-04-14
DE2527591A1 (de) 1976-01-15
JPS5913011B2 (ja) 1984-03-27
JPS511128A (en) 1976-01-07

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